In this study, the organic-inorganic composite elastic latex was prepared by using the polymerization process of pre-emulsification semi-continuous combined monomer dropping and investigated for the effect of the manner of the introduction of inorganic component and the amount of silica on the mechanical properties of the polymer film and water absorption. The results show that, when the sol is introduced with emulsion by the physical blending method and TEOS and A-151 are introduced together, the amount of them are respectively 1.5% and 9%, the organic-inorganic composite emulsion can be prepared. Meanwhile, if SiO2 is added by the way of TEOS and A-151, the best film properties of organic-inorganic acrylate flexible latex will be obtained .